a. Field of the Invention
The present invention pertains generally to roofing systems and more particularly to batten systems for tile roofs.
b. Description of the Background
Tile roofs provide an effective form of roofing that is long lasting, if installed properly, fire resistant and can have an aesthetic appearance. Tiles can be made of various different materials including fiberglass, cement, clay and other materials, all of which are generically referred to herein as “tiles”. For some time, tiles have been installed over plywood or oriented strand board (OSB) roof decking which is covered by an underlayment and regularly spaced battens, which are fastened through the underlayment to the roof deck. The tiles are then hung from and fastened to the roof battens. If precipitation penetrates the tile, the battens have a potential to dam water resulting in leakage of water through the penetrations of the underlayment as a result of fastening the battens to the roof deck and potential rotting of the battens that are placed in horizontal orientation, the dam water. This substantially threatens the lifespan of the roof.
As a solution to these problems, roofers adopted a lath and batten system, i.e., a counter-batten system in which vertically oriented battens are nailed to a felt covered roof with spacings of anywhere from 16 to 24 inches and horizontally oriented battens are nailed to the vertically oriented battens at spacings that satisfy the overlap dimensions of the tiles. These types of counter-batten systems allow water that seeps through the tiles to flow along the felt and not be dammed by horizontally oriented battens that are nailed directly to the roof. In other words, this type of counter-batten system allowed the free flow of water that penetrates the tiles along the underlayment without being substantially, impeded. In addition, the counter-batten systems create an airspace that provides insulating qualities and mediates the transmission of heat to and from the roof tile. As such, the heat transferred between the roof and the rest of the structure is mediated. In climates where snow can accumulate on the roof surface, this effect reduces the severity of the freeze/thaw cycles that occur on a roof, which can result in damming of water.
However, installation of these types of systems is labor intensive and time consuming. In addition, the spacing of the vertically oriented battens is normally controlled by local building codes. In order to reduce the amount of material used, installers typically install the vertical battens at the maximum width allowed by the building code. This requires careful measuring to ensure that the spacing of the vertically oriented battens does not exceed the maximum spacing allowed by code. If these measurements are not carefully made, the spacing of the vertically oriented battens can exceed the maximum spacing allowed which can, in some instances, result in the building inspector requiring that the roof be removed and reinstalled in accordance with code. Shims can be used to also reduce material costs. However, the same problems are involved with the installation of shims at distances that do not exceed code requirements.
In addition, wooden battens and shims are susceptible to rot in the moist environment of the roof system. As a result, the entire roof system must be replaced periodically because the counter-batten system tends to rot as a result of the naturally moist environment under the tiles. The vertically oriented battens in a counter-batten system and the shims in a shim system are both directly nailed to the felt on the roof and have constant contact with water that flows along the felt. As a result, the vertically oriented battens, in a counter-batten system, and the shims, in a shim system, do not have an extended life cycle.
In addition to the careful measurements that must be made when installing the vertically oriented batten systems, even more precise measurements must be made when installing the horizontal battens. After the proper spacing of horizontal battens is determined at each edge of the roof, a snap line must be used to mark the proper location of the horizontal battens, considering the allowable overlap of the tile. Few battens are straight enough and long enough to individually span the horizontal distance of the roof. Once the chalk snap lines have been placed on the roof, the horizontal battens can be installed. For example, a 14 inch spacing between horizontally oriented battens is typically a suitable spacing for most tiles. This process is a time consuming and labor intensive process that increases the expense of installation of tile roof systems.